easy ciphers

Easy Ciphers Tools:
cryptography lectures
popular ciphers:



















Caesar cipher

Caesar cipher, is one of the simplest and most widely known encryption techniques. The transformation can be represented by aligning two alphabets, the cipher alphabet is the plain alphabet rotated left or right by some number of positions.

When encrypting, a person looks up each letter of the message in the 'plain' line and writes down the corresponding letter in the 'cipher' line. Deciphering is done in reverse.
The encryption can also be represented using modular arithmetic by first transforming the letters into numbers, according to the scheme, A = 0, B = 1,..., Z = 25. Encryption of a letter x by a shift n can be described mathematically as

Plaintext: shaduf
cipher variations:
tibevg ujcfwh vkdgxi wlehyj xmfizk
yngjal zohkbm apilcn bqjmdo crknep
dslofq etmpgr funqhs gvorit hwpsju
ixqtkv jyrulw kzsvmx latwny mbuxoz
ncvypa odwzqb pexarc qfybsd rgzcte

Decryption is performed similarly,

(There are different definitions for the modulo operation. In the above, the result is in the range 0...25. I.e., if x+n or x-n are not in the range 0...25, we have to subtract or add 26.)
Read more ...
Atbash Cipher

Atbash is an ancient encryption system created in the Middle East. It was originally used in the Hebrew language.
The Atbash cipher is a simple substitution cipher that relies on transposing all the letters in the alphabet such that the resulting alphabet is backwards.
The first letter is replaced with the last letter, the second with the second-last, and so on.
An example plaintext to ciphertext using Atbash:
Plain: shaduf
Cipher: hszwfu

Read more ...


Baconian Cipher

To encode a message, each letter of the plaintext is replaced by a group of five of the letters 'A' or 'B'. This replacement is done according to the alphabet of the Baconian cipher, shown below.
a   AAAAA   g    AABBA     m    ABABB   s    BAAAB     y    BABBA
b   AAAAB   h    AABBB     n    ABBAA   t    BAABA     z    BABBB
c   AAABA   i    ABAAA     o    ABBAB   u    BAABB 
d   AAABB   j    BBBAA     p    ABBBA   v    BBBAB
e   AABAA   k    ABAAB     q    ABBBB   w    BABAA
f   AABAB   l    ABABA     r    BAAAA   x    BABAB

Plain: shaduf

Read more ...


Affine Cipher
In the affine cipher the letters of an alphabet of size m are first mapped to the integers in the range 0..m - 1. It then uses modular arithmetic to transform the integer that each plaintext letter corresponds to into another integer that correspond to a ciphertext letter. The encryption function for a single letter is

where modulus m is the size of the alphabet and a and b are the key of the cipher. The value a must be chosen such that a and m are coprime.
Considering the specific case of encrypting messages in English (i.e. m = 26), there are a total of 286 non-trivial affine ciphers, not counting the 26 trivial Caesar ciphers. This number comes from the fact there are 12 numbers that are coprime with 26 that are less than 26 (these are the possible values of a). Each value of a can have 26 different addition shifts (the b value) ; therefore, there are 12*26 or 312 possible keys.
Plaintext: shaduf
cipher variations:

The decryption function is

where a - 1 is the modular multiplicative inverse of a modulo m. I.e., it satisfies the equation

The multiplicative inverse of a only exists if a and m are coprime. Hence without the restriction on a decryption might not be possible. It can be shown as follows that decryption function is the inverse of the encryption function,

Read more ...


ROT13 Cipher
Applying ROT13 to a piece of text merely requires examining its alphabetic characters and replacing each one by the letter 13 places further along in the alphabet, wrapping back to the beginning if necessary. A becomes N, B becomes O, and so on up to M, which becomes Z, then the sequence continues at the beginning of the alphabet: N becomes A, O becomes B, and so on to Z, which becomes M. Only those letters which occur in the English alphabet are affected; numbers, symbols, whitespace, and all other characters are left unchanged. Because there are 26 letters in the English alphabet and 26 = 2 * 13, the ROT13 function is its own inverse:

ROT13(ROT13(x)) = x for any basic Latin-alphabet text x

An example plaintext to ciphertext using ROT13:

Plain: shaduf
Cipher: funqhs

Read more ...


Polybius Square

A Polybius Square is a table that allows someone to translate letters into numbers. To give a small level of encryption, this table can be randomized and shared with the recipient. In order to fit the 26 letters of the alphabet into the 25 spots created by the table, the letters i and j are usually combined.
1 2 3 4 5
1 A B C D E
2 F G H I/J K
3 L M N O P
4 Q R S T U
5 V W X Y Z

Basic Form:
Plain: shaduf
Cipher: 343211415412

Extended Methods:
Method #1

Plaintext: shaduf
method variations:

Method #2
Bifid cipher
The message is converted to its coordinates in the usual manner, but they are written vertically beneath:
s h a d u f 
3 3 1 4 5 1 
4 2 1 1 4 2 
They are then read out in rows:
Then divided up into pairs again, and the pairs turned back into letters using the square:
Plain: shaduf
Cipher: nqeiai

Read more ...
Method #3

Plaintext: shaduf
method variations:
obqvdm bqvdmo qvdmob
vdmobq dmobqv mobqvd

Read more ...[RUS] , [EN]


Permutation Cipher
In classical cryptography, a permutation cipher is a transposition cipher in which the key is a permutation. To apply a cipher, a random permutation of size E is generated (the larger the value of E the more secure the cipher). The plaintext is then broken into segments of size E and the letters within that segment are permuted according to this key.
In theory, any transposition cipher can be viewed as a permutation cipher where E is equal to the length of the plaintext; this is too cumbersome a generalisation to use in actual practice, however.
The idea behind a permutation cipher is to keep the plaintext characters unchanged, butalter their positions by rearrangement using a permutation
This cipher is defined as:
Let m be a positive integer, and K consist of all permutations of {1,...,m}
For a key (permutation) , define:
The encryption function
The decryption function
A small example, assuming m = 6, and the key is the permutation :

The first row is the value of i, and the second row is the corresponding value of (i)
The inverse permutation, is constructed by interchanging the two rows, andrearranging the columns so that the first row is in increasing order, Therefore, is:

Total variation formula:

e = 2,718281828 , n - plaintext length

Plaintext: shaduf

all 720 cipher variations:
shaduf shadfu shaudf shaufd shafud shafdu shdauf shdafu shduaf shdufa shdfua
shdfau shudaf shudfa shuadf shuafd shufad shufda shfdua shfdau shfuda shfuad
shfaud shfadu sahduf sahdfu sahudf sahufd sahfud sahfdu sadhuf sadhfu saduhf
sadufh sadfuh sadfhu saudhf saudfh sauhdf sauhfd saufhd saufdh safduh safdhu
safudh safuhd safhud safhdu sdahuf sdahfu sdauhf sdaufh sdafuh sdafhu sdhauf
sdhafu sdhuaf sdhufa sdhfua sdhfau sduhaf sduhfa sduahf sduafh sdufah sdufha
sdfhua sdfhau sdfuha sdfuah sdfauh sdfahu suadhf suadfh suahdf suahfd suafhd
suafdh sudahf sudafh sudhaf sudhfa sudfha sudfah suhdaf suhdfa suhadf suhafd
suhfad suhfda sufdha sufdah sufhda sufhad sufahd sufadh sfaduh sfadhu sfaudh
sfauhd sfahud sfahdu sfdauh sfdahu sfduah sfduha sfdhua sfdhau sfudah sfudha
sfuadh sfuahd sfuhad sfuhda sfhdua sfhdau sfhuda sfhuad sfhaud sfhadu hsaduf
hsadfu hsaudf hsaufd hsafud hsafdu hsdauf hsdafu hsduaf hsdufa hsdfua hsdfau
hsudaf hsudfa hsuadf hsuafd hsufad hsufda hsfdua hsfdau hsfuda hsfuad hsfaud
hsfadu hasduf hasdfu hasudf hasufd hasfud hasfdu hadsuf hadsfu hadusf hadufs
hadfus hadfsu haudsf haudfs hausdf hausfd haufsd haufds hafdus hafdsu hafuds
hafusd hafsud hafsdu hdasuf hdasfu hdausf hdaufs hdafus hdafsu hdsauf hdsafu
hdsuaf hdsufa hdsfua hdsfau hdusaf hdusfa hduasf hduafs hdufas hdufsa hdfsua
hdfsau hdfusa hdfuas hdfaus hdfasu huadsf huadfs huasdf huasfd huafsd huafds
hudasf hudafs hudsaf hudsfa hudfsa hudfas husdaf husdfa husadf husafd husfad
husfda hufdsa hufdas hufsda hufsad hufasd hufads hfadus hfadsu hfauds hfausd
hfasud hfasdu hfdaus hfdasu hfduas hfdusa hfdsua hfdsau hfudas hfudsa hfuads
hfuasd hfusad hfusda hfsdua hfsdau hfsuda hfsuad hfsaud hfsadu ahsduf ahsdfu
ahsudf ahsufd ahsfud ahsfdu ahdsuf ahdsfu ahdusf ahdufs ahdfus ahdfsu ahudsf
ahudfs ahusdf ahusfd ahufsd ahufds ahfdus ahfdsu ahfuds ahfusd ahfsud ahfsdu
ashduf ashdfu ashudf ashufd ashfud ashfdu asdhuf asdhfu asduhf asdufh asdfuh
asdfhu asudhf asudfh asuhdf asuhfd asufhd asufdh asfduh asfdhu asfudh asfuhd
asfhud asfhdu adshuf adshfu adsuhf adsufh adsfuh adsfhu adhsuf adhsfu adhusf
adhufs adhfus adhfsu aduhsf aduhfs adushf adusfh adufsh adufhs adfhus adfhsu
adfuhs adfush adfsuh adfshu ausdhf ausdfh aushdf aushfd ausfhd ausfdh audshf
audsfh audhsf audhfs audfhs audfsh auhdsf auhdfs auhsdf auhsfd auhfsd auhfds
aufdhs aufdsh aufhds aufhsd aufshd aufsdh afsduh afsdhu afsudh afsuhd afshud
afshdu afdsuh afdshu afdush afduhs afdhus afdhsu afudsh afudhs afusdh afushd
afuhsd afuhds afhdus afhdsu afhuds afhusd afhsud afhsdu dhasuf dhasfu dhausf
dhaufs dhafus dhafsu dhsauf dhsafu dhsuaf dhsufa dhsfua dhsfau dhusaf dhusfa
dhuasf dhuafs dhufas dhufsa dhfsua dhfsau dhfusa dhfuas dhfaus dhfasu dahsuf
dahsfu dahusf dahufs dahfus dahfsu dashuf dashfu dasuhf dasufh dasfuh dasfhu
daushf dausfh dauhsf dauhfs daufhs daufsh dafsuh dafshu dafush dafuhs dafhus
dafhsu dsahuf dsahfu dsauhf dsaufh dsafuh dsafhu dshauf dshafu dshuaf dshufa
dshfua dshfau dsuhaf dsuhfa dsuahf dsuafh dsufah dsufha dsfhua dsfhau dsfuha
dsfuah dsfauh dsfahu duashf duasfh duahsf duahfs duafhs duafsh dusahf dusafh
dushaf dushfa dusfha dusfah duhsaf duhsfa duhasf duhafs duhfas duhfsa dufsha
dufsah dufhsa dufhas dufahs dufash dfasuh dfashu dfaush dfauhs dfahus dfahsu
dfsauh dfsahu dfsuah dfsuha dfshua dfshau dfusah dfusha dfuash dfuahs dfuhas
dfuhsa dfhsua dfhsau dfhusa dfhuas dfhaus dfhasu uhadsf uhadfs uhasdf uhasfd
uhafsd uhafds uhdasf uhdafs uhdsaf uhdsfa uhdfsa uhdfas uhsdaf uhsdfa uhsadf
uhsafd uhsfad uhsfda uhfdsa uhfdas uhfsda uhfsad uhfasd uhfads uahdsf uahdfs
uahsdf uahsfd uahfsd uahfds uadhsf uadhfs uadshf uadsfh uadfsh uadfhs uasdhf
uasdfh uashdf uashfd uasfhd uasfdh uafdsh uafdhs uafsdh uafshd uafhsd uafhds
udahsf udahfs udashf udasfh udafsh udafhs udhasf udhafs udhsaf udhsfa udhfsa
udhfas udshaf udshfa udsahf udsafh udsfah udsfha udfhsa udfhas udfsha udfsah
udfash udfahs usadhf usadfh usahdf usahfd usafhd usafdh usdahf usdafh usdhaf
usdhfa usdfha usdfah ushdaf ushdfa ushadf ushafd ushfad ushfda usfdha usfdah
usfhda usfhad usfahd usfadh ufadsh ufadhs ufasdh ufashd ufahsd ufahds ufdash
ufdahs ufdsah ufdsha ufdhsa ufdhas ufsdah ufsdha ufsadh ufsahd ufshad ufshda
ufhdsa ufhdas ufhsda ufhsad ufhasd ufhads fhadus fhadsu fhauds fhausd fhasud
fhasdu fhdaus fhdasu fhduas fhdusa fhdsua fhdsau fhudas fhudsa fhuads fhuasd
fhusad fhusda fhsdua fhsdau fhsuda fhsuad fhsaud fhsadu fahdus fahdsu fahuds
fahusd fahsud fahsdu fadhus fadhsu faduhs fadush fadsuh fadshu faudhs faudsh
fauhds fauhsd faushd fausdh fasduh fasdhu fasudh fasuhd fashud fashdu fdahus
fdahsu fdauhs fdaush fdasuh fdashu fdhaus fdhasu fdhuas fdhusa fdhsua fdhsau
fduhas fduhsa fduahs fduash fdusah fdusha fdshua fdshau fdsuha fdsuah fdsauh
fdsahu fuadhs fuadsh fuahds fuahsd fuashd fuasdh fudahs fudash fudhas fudhsa
fudsha fudsah fuhdas fuhdsa fuhads fuhasd fuhsad fuhsda fusdha fusdah fushda
fushad fusahd fusadh fsaduh fsadhu fsaudh fsauhd fsahud fsahdu fsdauh fsdahu
fsduah fsduha fsdhua fsdhau fsudah fsudha fsuadh fsuahd fsuhad fsuhda fshdua
fshdau fshuda fshuad fshaud fshadu

Read more ...[1] , [2] , [3]

History of cryptography
2011 Easy Ciphers. All rights reserved. contact us